Louis schuleb



(No Model.) v

L. SCHULER. HYDRAULIG DRAWING PRESS.

No.57o,o6s. Patented oct, 27, 1896.

UNITED STAT-Es PATENT "OFFICE,

LOUIS SOI-IULER, OF GOEPPINGEN, GERMANY.

HYDRAULIC DRAWING-PRESS.

SPECIFICATION forming part of Letters Patent No. 570,063, dated October 2'?, 1896.

Application iiled March 30,1895. Serial No. 543,839. (No model.) Patented in Austria October 3l, 1894, No. 45/170,l in Belgium November 5, 1894, No. 112,562, and in England November 13, 1894, No. 21,942.

To @ZZ whom t may con/cern.-

Be it known that I, LoUIs SCHULER, a subject of the King of Wrtemberg, residing at Goeppingen, Kingdom of Viirtemberw` Germany, have invented a certain new and useful Improved Hydraulic Drawing-Press, (for which I have obtained Letters Patent in Belgium, No. 112,562, dated November 5,1894; in Austria, No. 45 170, dated October 3l, 1894, and in Great Britain, No. 21,942, dated November 13, 1594,) of which the following is a specification.

My invention consists in the novel features hereinafter described, and particularly pointed out in the claims.

To enable my invention to be fully understood, I will describe how it can be carried into practice by reference to the accompanying drawing, which represents a vertical section of a hydraulic drawing-press constructed according to my invention.

A piston b is arranged to slide in the frame a of the press, and in this piston is a second and smaller piston c. The outer piston b moves the table (l and plate-holder respectively, while the inner piston c moves the drawing-die o.

On the under side of the outer piston is provided a valve e, which is pressed up to the piston by the action of a spring 'e' as soon as the piston arrives at the lowest point lof its stroke.

The valve e is provided with a small opening e2, through which water under pressure may enter between Vthe valve and the lower surface of the piston c. The valve e is guided by a piston-rod r', the upper end of which is rigidly connected with the inner piston c, while the lower end is provided with a piston r2, which is adapted to move up and down within a small cylinder r, screwed to the frame a.

The water under pressure is led through a valve f in the direction of the arrow t' and led off by a valve g. These valves f g are so connected with each other that when one is open the other is shut, and conversely. If, for example, the valve f be pressed home on its seating, the valve gis raised from its seating by the compression of the spring s. If, on the other hand, the valve f be raised from its seating, the spring s drives the valve g back and the latter is closed.

The movement of the outer piston b and of the table d is limited above by clamping-nuts Je 7c and below by a stop Z, while the inner piston c or the drawing-die fr, respectively, strike on the throw-out plate m in the upstroke. The latter is connected to the crossbar n, which cornes into contact with the stop 0 on the guide-rod p as the upstroke proceeds. On the lower end of the rod p there is secured a bell-crank lever q, rotating on a pivot q, which is connected with the valve f.

At the beginning of the operation of the press the two pistons are in the lowest position. The valve c is closed and remains in that position by reason of the water-pressure acting upon it. This pressure is, of course, greater than the weight of the inner piston and the counter-pressure of the smaller piston r2. Thus the outer piston b is able to raise the inner piston c with it. For this reason the two pistons begin their upward movement at the same time, but the outer one is arrested as soon as the plate-holder t, which is connected with it, strikes against the matrix'u or the table d comes into contact with the clamping-nuts It 7o'.

During the upward movement of the twov pistons b c some water under pressure has entered through the opening e2 between the valve and the lower surface of the piston c, so as to fill out that space. As soon as the strokev against the matrix or against thev clamping-nuts takes place the pressure of the water behind the valve is augmented until it is compensated after a short time bythe pressure before the valve, so that the valve falls down by reason of its own gravity. In this manner the water under pressure can freely enter below the piston c, so that the latter, and with it the drawing-die, continues its upward movement until the stop 0 is raised by the cross-bar n.

The action of the drawing-press is thereby reversed, since the rod p is raised and the vvalve f is closed by the action of the bellcrank lever q. At the saine moment, however, the valve g is opened, so that the water under pressure is able to issue from'the piston, and the latter and the drawing-tools are IOO 2 5 used as a water-receptacle 72..

ro ically as soon as it encounters any opposition to its downward motion, whether from the adhesion of the drawn vessel to the die or from any other increase of friction, I provide thepiston r2, already referred to. The downward motion of the inner piston c would in the case supposed proceed as follows: As soon as the outer piston b, and with it the table d, has reached its lowest point the reversal is effected as above described and the zo water under pressure flows in, whereby on the one hand the piston 'r2 is drawn down, while on the other hand the upward Inovement of the piston i) is effected.

The lower part of the frame a could be lVhen it is desired to accelerate the downward movement of the pistons, I may effect this by sucking the outliowin g waste water t-hrough the airtight water-space h, which is first deprived 3o of the water under pressure by a pump,

whereby a vacuum-chamber is formed.

It is evident that the form of the valves c, f, and g may undergo slight modications without altering anything of the substance of the invention.

lVhat I claim, and desire to secure by Letters Patent, is-

l. A hydraulic drawing-press comprising the frame two pistons iitting the one into 4o the other, a valve e closing the end of the outer piston and having an opening e2 to allow the water to lill the space between the end of the inner piston and the end of the outer piston as closed by said valve, the matri'x u, fixed to the frame, the plate-holdert ing the valve a against the end of the outer piston whereby said valve will leave its seat as a consequence of the inflow of sufficient water to the space between it and the end of the inner piston, substantially as described.

2. In combination, the inner and outer pistons, the frame carrying the same, the cylinder into which the pistons extend, the inlet and outlet Valves f, g, arranged to be seated alternately whereby when the inlet-Valve is closed the discharge-valve is opened, means for operating the inlet-valve and connections from both the inner and outer pistons whereby upon the end of the working stroke of the inner piston the inlet-valve will be closed and upon the return of the outer piston the inlet-Valve will be opened, substantially as described.

A hydraulic press comprising a cylinder, an outer hollow piston, an inner piston, the perforated Valve e for closing the end of the hollow piston a supplemental piston r2 with its cylinder, said piston being connected with the inner piston by its rod and valves controlling the supply of water to the main and supplemental cylinders, said supplemental piston being arranged to return the inner piston to normal position, and having the valve e thereon substantially as described.

l. In combination, the cylinder, the outer hollow piston, with means for closn g its end, the inner piston, the supplemental piston r2 connected to the inner piston to return the same, the supplemental cylinder for the piston r2 and Valves controlling the liquid-pressure to the main and supplemental cylinders, said supplemental piston i returning the inner piston while the hollow piston is closed by its closing means, substantially as described.

In witness whereof Ihave hereunto set my hand, in presence of two witnesses, at Stuttgart, Kingdom of llliirtemberg, Germany, this 24th day of January, in the year 1895.

LOUIS SCHULER. lVitnesses:

AUG. WEssLINGEn, ALBERT KEPPELMAYR. 

